Nitric oxide has found to be useful in a number of ways for treatment of disease, particularly cardiac and respiratory ailments. Previous systems for producing NO and delivering the NO gas to a patient have a number of disadvantages. For example, tank-based systems required large tanks of NO gas at a high concentration and pressure. When treatment using this system is paused, NO in the circuit stalls and converts into NO2, requiring the user to purge the manual ventilation circuit before resuming manual ventilation. Synthesizing NO from NO2 or N2O4 requires the handling of toxic chemicals. Prior electric generation systems involve generating plasma in the main flow of air to be delivered to patients, or pumped through a delivery tube.
Calibration of current systems can also be difficult, as a user is required to connect high pressure gas canisters containing calibration gas to the system. Calibration gases typically include NO, NO2, and O2. For one concentration and one gas at a time, gas is flowed through the sensor chamber to provide a known input. This manual calibration can take roughly 15 minutes or more of trained personnel time. When tank-based systems flow, they release high-concentration (approximately 800 ppm) NO into the ventilation system. When treatment with a tank-based system is paused, NO in the manual circuit (Ambu-bag or equivalent) stalls and converts into NO, requiring the user to purge the manual ventilation device circuit before resuming manual ventilation.